scarabeus

Hi all!

I've been in the hobby years and years, but last year has been the first one with metal-halide lamps. There's a picture of the tank attached, it is 60cm high 325litres/85gallons, plants still waiting very much to grow in after a rebuild. Lighted by 2x150w/6500K metal halide lamps.
If I did my homework correctly this gives pretty hefty 3,5 watts of lighting power per gallon.

My question is, what are the most important things I should take into consideration (to avoid problems) when dealing with this kind of illumination?

I've had two little algae blooms that were dealt with a blackout of 72hrs.
I'm still planning to add lots of low growing plants in the fore/middle-ground and maybe look for 1-2 species to fill in the background as well.
Lighting period is roughly 3-4hrs in the morning, 2-3hrs break and another 3-4hrs in the evening.

I'm dosing 10ml of Easylife-Easycarbo CO2 per day, changing water 100litres/26gallons per week and fertilising 30ml of Easylife-Profit and 15ml of Easylife-Ferro when changing the water. Weekly, that is.
Substrate is mixture of Prosoil-plant substrate and black sand/gravel.

If somebody wonders what's with the aluminium foil, it's because my 7months old son LOVES playing close to the aquarium and the lamps are way too bright for his eyes. =)

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Fishguy10

Hello,

I have a tank with about 3.3 wpg of 6500K T5 light. T5 and metal hallide definetly aren't the same thing, but I might be able to help a little.

I used to have problems with algae, but the algae had basically stopped growing entirely. It has slowly started to return because I've been kind of busy and I've fallen behind a little on my normal schedule.

Anyways, the first thing that helped was getting CO2. If you have intense lighting and plan on growing red plants, fast growers, or foreground plants, CO2 really does help a lot. The plants look so much healthier, reds develop brighter and more vivid colors, and plants pearl as well. CO2 systems are expensive, but they really do make a big difference. Just something to think about, I know that I'm glad that I decided to get one.

Even after getting CO2 though, there was still some algae, although there was less of it and it didn't look as thick. The second thing that really killed the algae was starting to dose the tank. I tried a couple of different fertilization methods, but the one that really worked best for me was EI. I was a little skeptical at first and it seemed kind of wastefull in terms of water and ferts, but it really worked well for me. I'm not exactly sure if the actual fertilizers are responsible for the dramatic decrease in algae, but the system works for me. I personally think that it might be the huge 50% water change each week that really kills and prevents the algae. The algae had completely stopped growing, and then I missed two or three weeks of dosing and water changes and the algae has started growing back. I'm starting over again, so hopefully the algae will once again go away.

If you want to try or read more about EI, the fertilizing forum here has a great guide for it. The 50% water change might be a little difficult since I'm assuming your tank is somewhere around 85 gallons, so you would have to be changing about 40 gallons every week. Other than the water change though, it's a fairly easy system to follow.

I'm not sure if you have a soil substrate, because I'm not familiar with Prosoil, and I'm not exactly sure if dosing in the water column is necessary if you have a soil substrate, but EI realy does work well for me.

I hope this helps, and good luck with your high-light tank.

scarabeus

Thanks Fishguy!

In your opinion, is there a big difference between added liquid CO2 (which I'm using now) and somekind of diffusor?

krcsasha

What do you think about LED strips?

Fishguy10

Scarabeus -

I started off dosing Excel in my tank and it was working pretty well. When I switched over to pressurized CO2 and stopped dosing Excel, I noticed a difference immediately. First off, most of my plants, especially my HC, started pearling the very first day I started using CO2. From there, all of my plants started growing denser and healthier-looking growth and my Ludwigia started to turn much redder. My HC started spreading faster and growing together more, and it's new growth was a very nice light green. Overall, everything just looked healthier, more colorful, and better in general and all of the plants started growing faster.

Krcsasha -

I find LEDs very interesting. They seem to have a lot of benefits, although they haven't really been widely used enough to report on the growth that they produce. From what I've seen and heard, good LED fixtures are usually expensive and some of the cheaper fixtures don't work as well. If you want to find out more about them, there are a few threads here about LEDs and you could probably also look at reviews on specific fixtures that you're interested in.

BogdanHojbota

I am using HQI 2*150watt ( metal halide) lamp over an year, at my aquarium 320 liters ( 130*45*55h).
using this light( over 20000 lumens) - means a lot of light.
Without presurized Co2 and proper nutrients level especialy macro, using HQI is suicide

You also need much more plants in your aquarium, to balance light vs nutrient uptake.
Fewer plants, means high risk of algae. I have trimed 50% of my plants and , i keept constant light and ferts ( bad mistake) - in short time fuzz algae, was all over in the aquarium.

HQI, is like a race car, more light => more fuel the plants will burn ( Co2, micro & macro nutrients)

BUT, the main problem of the HQI - is plant color. Under HQI light, red plants are not red, they become green. I have tryed multiple combinations of bulbs, ferts, lighting period, but without succes.

http://imageshack.us/photo/my-images/221/02102011o.jpg


http://imageshack.us/photo/my-images/21/img6515mb.jpg
http://imageshack.us/photo/my-images/35/img6519f.jpg
http://imageshack.us/photo/my-images/808/img6521r.jpg


http://www.youtube.com/watch?feature...&v=elEx1VPjVQ0

Fishguy10

Bogdan -

I'm surprised that you can't get red color with your lights. Higher light intensity usually increases redness, at least from what I've seen. If you've already tried different bulbs, photo period, and different fert ratios it must be something else. Do you think it could be caused by either a lack of iron or an excess of nitrates? Some people think that iron levels dramatically affect red color in plants, so you could try dosing some extra iron and see what happens. Some red plants also color up more when the nitrate levels in the tank are low. Have you tried either of those?

scarabeus

Thanks for all the thoughts!

Been adding more plants, and gradually decreasing the amount of Elodea canadensis as the Ludwigias and the creeping Jenny are growing. Added iron-heavy ferti-sticks into the substrate every 20cm2. Trying to shoot for Glossostigma coverage on the bottom, but fish seem to think it's fun to watch the human replant them every second day.
Glad to see that pogostemon helferii seems to be finally kicking off.

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Fishguy10

Everything is looking good

I have some creeping jenny as well and it grows pretty fast sometimes, but it does seem to like being trimmed back. What species of Ludwigia is that by the way?

I've always liked the look of Pogostemon Helferi, and it's good to see that yours is growing. Good luck with the Glosso as well.